Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland.
Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland; Vital-IT, Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland.
Mol Metab. 2020 May;35:100958. doi: 10.1016/j.molmet.2020.02.001. Epub 2020 Feb 6.
In the pathogenesis of type 2 diabetes, development of insulin resistance triggers an increase in pancreatic β-cell insulin secretion capacity and β-cell number. Failure of this compensatory mechanism is caused by a dedifferentiation of β-cells, which leads to insufficient insulin secretion and diabetic hyperglycemia. The β-cell factors that normally protect against dedifferentiation remain poorly defined. Here, through a systems biology approach, we identify the transcription factor Klf6 as a regulator of β-cell adaptation to metabolic stress.
We used a β-cell specific Klf6 knockout mouse model to investigate whether Klf6 may be a potential regulator of β-cell adaptation to a metabolic stress.
We show that inactivation of Klf6 in β-cells blunts their proliferation induced by the insulin resistance of pregnancy, high-fat high-sucrose feeding, and insulin receptor antagonism. Transcriptomic analysis showed that Klf6 controls the expression of β-cell proliferation genes and, in the presence of insulin resistance, it prevents the down-expression of genes controlling mature β-cell identity and the induction of disallowed genes that impair insulin secretion. Its expression also limits the transdifferentiation of β-cells into α-cells.
Our study identifies a new transcription factor that protects β-cells against dedifferentiation, and which may be targeted to prevent diabetes development.
在 2 型糖尿病的发病机制中,胰岛素抵抗的发展引发了胰腺β细胞胰岛素分泌能力和β细胞数量的增加。这种代偿机制的失败是由于β细胞的去分化引起的,导致胰岛素分泌不足和糖尿病高血糖。正常情况下保护β细胞免受去分化的β细胞因子仍未得到很好的定义。在这里,我们通过系统生物学方法,确定转录因子 Klf6 是β细胞适应代谢应激的调节因子。
我们使用β细胞特异性 Klf6 敲除小鼠模型来研究 Klf6 是否可能是β细胞适应代谢应激的潜在调节剂。
我们表明,β细胞中 Klf6 的失活削弱了它们对妊娠、高脂肪高蔗糖喂养和胰岛素受体拮抗剂引起的胰岛素抵抗的增殖。转录组分析表明,Klf6 控制β细胞增殖基因的表达,并且在存在胰岛素抵抗的情况下,它防止控制成熟β细胞特征的基因的下调和诱导破坏胰岛素分泌的不允许基因。它的表达还限制了β细胞向α细胞的转分化。
我们的研究确定了一种新的转录因子,它可以保护β细胞免受去分化,并且可能成为预防糖尿病发展的靶点。